Diesters of halo-substituted alkyloxyalkylphosphonates

ABSTRACT

Novel compositions of matter comprising diesters of halosubstituted alkyloxyalkylphosphonates containing at least two halogen atoms as exemplified by dimethyl 3-chloro-2,3dibromopropoxymethylphosphonates are utilized as components in preparing compounds such as plastics, polymers, resins, etc. and will impart desirable physical characteristics of flame retardance or fire resistance to these compounds.

United States Patent Benghiat [45] Oct. 24, 1972 [54] DIESTERS OFHALO-SUBSTITUTED OTHER PUBLICATIONS ALKYLOXYALKYLPHOSPHONATES IndexChemieus, Vol. 28, No. 7, Feb. 2, 1968, Item [72] Inventor: IsaacBenghiat, New City, N.Y. No. 91161..

[73] Asslgnee: 322x23 cumpmy Primary Examiner-Joseph Rebold AssistantExaminer-Anton H. Sutto [22] Filed: Dec. 29, 1969 Attorney-James R.Hoatson, Jr. and Raymond H. 211 Appl. No.: 888,966 Nels [57] ABSTRACT[52] US. Cl ..260/950, 117/156, 260/45.7 R,

Novel compositions of matter comprising diesters of 260/4297 260/612260/614 halo-substituted alkyloxyalkylphosphonates containing 7 at leasttwo halogen atoms as exemplified by dimethyl 7/403-chloro-2,3-dibromopropoxymethylphosphonates are utilized as componentsin preparing compounds such as plastics, polymers, resins, etc. and willimpart [56] References cued desirable physical characteristics of flameretardance FOREIGN PATENTS OR APPLICATIONS or fire resistance to thesecompounds- 8/1955 Canada ..260/950 6 Claims, No

DIESTERS OF HALO-SUBSTITUTED ALKYLOXYALKYLPHOSPHONATES This inventionrelates to novel compositions of matter comprising diesters ofhalo-substituted alkyloxyalkylphosphonates. More specifically, theinvention is concerned with these novel compounds which are alkyldiesters of halo-substituted alkyloxyalkylphosphonates which contain atleast two halogen atoms and to their use thereof as components offinished compositions of matter which possess a high degree of flameretardancy.

It has now been discovered that the flame retardancy or fire resistanceof many compounds such as polymers may be enhanced by the addition of adiester of a halosubstituted alkyloxyalkylphosphonate which contains atleast two halogen atoms. Some examples of compounds which may be admixedwith the phosphonate of the type hereinafter set forth in greater detailwill include plastics, polymers, resins as well as naturally occurringtextiles and fibers, specific examples of these compounds includingpolyolefins such as polyethylene, polypropylene, polystyrene andcopolymers thereof, polyesters, polyurethanes, polyphenyl ethers such aspolyphenylene oxides, polycarbonates, polyamides, polyoxymethylenes,polyalkylene oxides such as polyethylene oxide, polyacetals,polyacrylates, polymethacrylates, epoxy resins, copolymers or graftpolymers of acrylonitrile with styrenic olefins such asacrylonitrile-butadiene-styrene formulations (commonly known as ABS),both naturally occurring and synthetic rubber such as polyisoprene,polybutadiene, EPR rubber, SBR rubber, textiles, fibers, fabrics, saidtextiles, fibers and fabrics being both naturally occurring andsynthetic in nature, coatings, paints, varnishes, leathers, foam, etc.By combining these aforementioned compounds with a diester of apolyhalo-substituted alkylphosphonate of the'type hereinafter set forthin greater detail, the compounds will possess the desirably physicalcharacteristics of flame proofing or fire retardancy. These particularphysical characteristics will possess special advantages when preparingplastics, polymers, resins, various rubbers, textiles, etc. which willbe utilized in places which may be subjected to excessive heat or to theaction of a possible flame, such places including architectural panelsfor construction work, wall plugs for electrical connections,soundproofing material in walls, ceilings, etc., cushions for variousvehicle seats such as airplane seats, automobile seats, bus seats, etc.In addition, the compound when utilized as a constituent of paint,lacquer, varnishes, or protective coatings, films, etc. will also imparta flame resistancy to these compounds and, therefore, render themcommercially attractive as articles of commerce. In addition, it is alsocontemplated that the novel compositions of matter comprising a diester,and particularly a dialkyl ester of a halo-substitutedalkyloxyalkylphosphonate containing at least two halogen atoms may alsobe useful as insecticides, and particularly against houseflies.

It is therefore an object of this invention to provide novelcompositions of matter which possess desirable physical characteristicsor properties.

Another object of this invention is to provide novel compositions ofmatter possessing these desirable physical characteristics offlameproofing and fire retardancy whereby said compositions of mattermay be useful as components of finished important commercial articles ofmanufacture.

In one aspect an embodiment of this invention resides in a novelcomposition of matter comprising a diester of a halo-substitutedalkyloxyalkylphosphonate containing at least two halogen atoms.

Another embodiment of this invention resides in a flame retardantcomposition of matter comprising a polymer and an effectiveconcentration of a diester of a halo-substitutedalkyloxyalkylphosphonate containing at least two halogen atoms.

A specific embodiment of this invention is found in a novel compositionof matter comprising dimethyl 3-chloro-2,3dibromopropoxymethylophosphonate.

Another specific embodiment of this invention is found in a flameretardant composition of matter comprising an admixture of a polyesterand dimethyl 3- chloro-2,3-dibromopropoxymethylphosphonate.

Other objects and embodiments will be found in the following furtherdetailed description of the present invention.

As hereinbefore set forth the present invention is concerned with novelcompositions of matter which comprise diesters, and particularly dialkylesters of halo-substituted alkyloxyalkylphosphonates containing at leasttwo halogen atoms. The aforementioned novel compositions of matter willpossess the generic formula:

in which X is hydrogen or halogen atoms, preferably chlorine or bromine,R is an alkyl radical of from one to about five carbon atoms, R and R"are independently selected from the group consisting of hydrogen,halogen, lower alkyl of from one to five carbon atoms, cycloalkyl, aryl,aralkyl, alkaryl and halogenated derivatives thereof, and n is aninteger of from one to five,'there being at least two halogen atoms insaid compound.

Some representative specific examples of the novel compositions ofmatter of the present invention which possess the generic formulahereinbefore set forth will include dimethyl2-chloro-2,3-dibromopropoxymethylphosphonate, dimethyl 3-chloro-2,3-dibromopropoxymethylphosphonate, dimethyl 2,3-dichloropropoxymethylphosphonate, dimethyl 2,3-dibromopropoxymethylphosphonate, dimethyl 3-cyclohexyl-3-chloro-2,3-dibromopropoxymethylphosphonate, dimethyl3-cyclohexyl-2,3- dichloropropoxymethylphosphonate, dimethyl 3-cyclohexyl-2,3-dibromopropoxymethylphosphonate, dimethyl S-phenyl-2,3-dichloropropoxymethylphosphonate, dimethyl 3-phenyl-2,3-dibromopropoxymethylphosphonate, dimethyl3-(ptolyl)-2,3-dichloropropoxymethylphosphonate,

dimethyl 3-(p-tolyl)-2,3-dibromopropoxymethylphosphonate, dimethyl2,3-dichlorobutoxymethylphosphonate, dimethyl2,3-dibromobutoxymethylphosphonate, dimethyl 4-phenyl-3 ,4-

dichlorobutoxymethylphosphonate, dimethyltolyl)-2,3-dichlorobutoxymethylphosphonate,

dimethyl 4-phenyl-4-chloro-3,4-dibromobutoxymethylphosphonate, diethyl2-chloro-2,3- dibromopropoxymethylphosphonate, diethyl 3-chloro-2,3-dibromopropoxymethylphosphonate, diethyl 2,3-dichloropropoxymethylphosphonate, diethyl 2,3-dibromopropoxymethylphosphonate, diethyl 3-cyclohexyl-3-chloro-2,3-dibromopropoxymethylphosphonate, diethyl3-cyclohexyl-2,3- dichloropropoxymethylphosphonate, diethyl 3-cyclohexyl-2,3-dibromopropoxymethylphosphonate,

diethyl 3-phenyl-2,3-dichloropropoxymethylphosphonate, diethyl3-phenyl-2,3- dibrmopropoxymethylphosphonate, diethyl3-(ptolyl)-2,3-dichloropropoxymethylphosphonate, diethyl3-(p-tolyl)-2,3d-dibromopropoxymethylphosphonate, diethyl2,3-dichlorobutoxymethylphosphonate, diethyl2,3-dibr0mobutoxymethylphosphonate, diethyl 4-phenyl-3,4-dichlorobutoxymethylphosphonate, diethyl4-(p-tolyl)-2,3d-dichlorobutoxymethylphosphonate,

diethyl 4-ph enyl-4-chloro-3,4-dibromobutoxymethylphosphonate, dipropyl2-chloro-2,3- dibromopropoxymethylphosphonate, dipropyl 3-ch1oro-2,3-dibromopropoxymethylphosphonate,

dipropyl 2,3-dichr0propoxymethylphosphonate, dipropyl2,3-dibr0mopropoxymethylphosphonate, dipropyl3-cyclohexyl-3-chloro-2,3-dichloropropoxymethylphosphonate, dipropyl3-cyclohexyl-2,3-

dibromopropoxymethylphosphonate, dipropyl3-phenyl-2,3-dichloropropoxymethylphosphonate, dipropyl 3-phenyl-2,3-dibromopropoxymethylphosphonate,

dipropyl 3-(p-tolyl)-2,3-dichloropropoxymethylphosphonate, dipropyl3-(p-tolyl)-2,3- dibromopropoxymethylphosphonate, dipropyl 2,3-dichlorobutoxymethylphosphonate, dipropyl 2,3-

dibutyl 3-phenyl-2,3-dichloroprop0xymethylphosphonate, dibutyl3-phenyl-2,3- dibromopropoxymethylphosphonate, dibutyl3-(ptolyl)-2,3-dichloropropoxymethylphosphonate, dibutyl3-(p-tolyl)-2,3d-dibromopropoxymethylphosphonate, dibutyl2,3-dichlorobutoxymethylphosphonate, dibutyl2,3-dibr0mobutoxymethylphosphonate, dibutyl 4-phenyl-3,4-dichlorobutoxymethylphosphonate, dibutyl4-(p-tolyl)-2,3d-dichlorobutoxymethylphosphonate,

dibutyl 4-phenyl-4-chloro-3,4-dibromobutoxymethylphosphonate, dimethyl2-chloro-2,3- dibromopropoxyethylphosphonate, dimethyl 2,3-dichlor0propoxyethylphosphonate, dimethyl 3-cyclohexyl-3-chloro-2,3-dibromopropoxyethylphosphonate, dimethyl3-cyclohexyl-2,3- dibromopropoxyethylphosphonate, dimethyl 3-phenyl-2,3-dibromopropoxyethylphosphonate, dimethyl3-(ptolyl)-2,3-dibromopropoxyethylphosphonate, dimethyl2,3-dibromobutoxyethylphosphonate, dimethyl4-(ptolyl)-2,3-dichlorobutoxyethylphosphonate, diethyl 2-chloro-2,3-dibromopropoxyethylphosphonat, diethyl2,3-dichloropropoxymethylphosphonate, diethyl 3-cyclohexyl-3-chloro-2,3-dibromopropoxyethylphosphonate, diethyl3cyclohexyl-2,3- dibromopropoxyethylphosphonate, diethyl3-cyclohexyl-2,3-dibromopropoxyethylphosphonate, diethyl 3-phenyl-Z,3-dibromopropoxyethylphosphonate, diethyl3-(p-tolyl)-2,3-dibromopropoxyethylphosphonate, diethyl2,3-dibromobutoxyethylphosphonate, diethyl4-(-tolyl)-2,3-dich]orobutoxyethylphosphqnate, dipropyl2-chloro-2,3-dibromopropoxyethylphosphonate, dipropyl2,3-dichloropropoxyethylphosphonate, dipropyl 3-cyclohexyl-3-chloro-2,3-dibrombpropoxyethylphosphonate, dipropyl 3-cyclohexyl-Z,3-dibromopropoxyethylphosphonate dipropyl3-phenyl-2,3-dibromopropoxyethylphosphonate, dipropyl 3-(p-tolyl)-2,3-dibromopropoxyethylphosphonate, dipropyl 2,3-dibromobutoxyethylphosphonate, dipropyl 4-(p-tolyl)-2,3-dichlorobutoxyethylphosphonate, dibutyl 2-chloro-2,3-dibromopropoxyethylphosphonate, dibutyl 2,3-dichloropropoxyethylphosphonate, dibutyl3-cyclohexyl-3-chloro-2,3-dibromopropoxyethylphosphonate, dibutyl3-cyclohexyl-2,3-dibromopropoxyethylphosphonate, dibutyl 3-phenyl-2,3-dibromopropoxyethylphosphonate, dibutyl 3-(p-tolyl)-2,3-dibromopropoxyethylphosphonate, dibutyl 2,3-

dibromobutoxyethylphosphonate, dibutyl 4-(p-tolyl)-2,3-dichlorobutoxyethylphosphonate, dimethyl 3-chloro-2,3-dibromopropoxypropylphosphonate,

dimethyl 2,3-dibromopropoxypropylphosphonate, dimethyl3-cyclohexyl-2,3-dichloropropoxypropylphosphonate, dimethyl3-phenyl-2,3-

dichloropropoxypropylphosphonate, dimethyl3-(ptolyl)-2,3-dichloropropoxypropylphosphonate, dimethyl2,3-dichlorobutoxypropylphosphonate, dimethyl4-phenyl-3,4-dichlorobutoxypropylphosphonate,dimethyl-4-phenyl-4-chloro-3,4- dibromobutoxypropylphosphonate, dithyl3-chloro- 2,3-dibromopropoxypropylphosphonate, diethyl 2,3-dibromopropoxypropylphosphonate, -diethyl 3-cyclohexyl-2,3-dichloropropoxypropylphosphonate, diethyl3-phenyl-2,3-dichloropr0poxypropylphosphonate, diethyl 3-(p-tolyl)-2,3-dichloropropoxypropylphosphonate, diethyl 2,3-dichlorobutoxypropylphosphonate, diethyl 4-phenyl-3,4-dichlorobutoxypropylphosphonate, diethyl-4-phenyl-4-chloro-3,4-dibromobutoxypropylphosphonate, dipropyl3-chloro-2,3- dibromopropoxypropylphosphonate, dipropyl 2,3-dibromopropoxypropylphosphonate, dipropyl 3-cyclohexyl-Z,3-dichloropropoxypropylphosphonate,

dipropyl 3-phenyl-2,S-dichloropropoxypropylphosphoqate, dipropyl3-(p-tolyl)-2,3- dichloropropoxypropylphosphonate, dipropyl 2,3-dichlorobutoxypropylphosphonate, dipropyl 4-phenyl-3,4-dichlorobutoxypropylphosphonate, dipropyl 4-phenyl-4-chloro-3,4dibromobutoxypropylphosphonate, dibutyl 3-chloro-2,3-dibromopropoxypropylphosphonate, dibutyl 2,3-dibromopropoxypropylphosphonate, dibutyl 3-cyclohexyl-Z,3-dichloropropoxypropylphosphonate, dibutyl3-phenyl-2,3-dichloropropoxypropylphosphonate, dibutyl 3-(p-tolyl)-2,3-dichloropropoxypropylphosphonate, dibutyl 2,3-dichlorobutoxypropylphosphonate, dibutyl 4-phenyl-3,4-dichlorobutoxypropylphosphonate, dibutyl 4-phenyl-4-chloro-3,4-dibromobutoxypropylphosphonate, the correspondingdiethyl-, dipropyl, dibutyl-, and dimethylof the correspondinghalo-substituted phosphonates, etc. It is to be understood that theaforementioned compounds are only representative of the novelcompositions of matter, and that the present invention is notnecessarily limited thereto.

The novel compositions of matter of the type hereinbefore set forth maybe prepared by reacting an alkenyloxyalkyl halide with a trialkylphosphite in the presence of an organic solvent at condensationconditions. For the purposes of this invention the halide compound willbe defined as a compound in which the alkenyl portion of the compoundwill contain an ethylenic unsaturation and may, if so desired, alsocontain halogen substituents, said halogen substituents being eitherchlorine or bromine. The aforementioned condensation conditions willinclude a temperature in the range of from about 100C. to about 200C.,and preferably at the reflux temperature of the particular solvent ifone is employed in the reaction. Generally speaking, the reaction may beeffected at pressures ranging from atmospheric up to about 50atmospheres or more, the preferred pressure being atmospheric. Somespecific examples of alkenyloxyalkyl halides which may be condensed witha trialkyl phosphite will include allyloxymethyl chloride,propenyloxymethyl chloride, 2-chloroallyloxymethyl chloride,3-chloroallyloxymethyl chloride, 2-bromoallyloxymethyl chloride,3-bromoallyloxymethyl chloride, 2- chloropropenyloxymethyl chloride,butenyloxymethyl chloride, 3-chlorobutenyloxymethyl chloride, 3-bromobutenyloxymethyl chloride, 3-phenylallyloxymethyl chloride,3-cyclohexylallyloxymethyl chloride, 3-p-tolyl-allyloxymethyl chloride,3-phenyl-2-chloroallyloxymethyl chloride,3-phenyl-2-.bromoallyloxymethyl chloride, allyloxyethyl chloride,propenyloxyethyl chloride, 2-chloroallyloxyethyl chloride, 3-chloroallyloxyethyl chloride, 2-bromoallyloxyethyl chloride,3-bromoallyloxyethyl chloride, 2- chloropropenyloxyethyl chloride,butenyloxyethyl chloride, 3-chlorobutenyloxyethyl chloride, 3-bromobutenyloxyethyl chloride, 3-phenylallyloxyethyl chloride,3-cyclohexylallyloxyethyl chloride, 3-ptolylallyloxyethyl chloride,3-phenyl-2-chloroallyloxyethyl chloride, 3-phenyl-2-bromoallyloxyethylchloride, allyloxypropyl chloride, propenyloxypropyl chloride,2-chloroallyloxypropyl chloride, 3-chloroallyloxypropyl chloride,2bromoallyloxypropyl chloride, 3-bromoallyloxypropyl chloride,2-chloropropenyloxypropyl chloride, butenyloxypropyl chloride, 3-chlorobutenyloxypropyl chloride, 3-bromobutenyloxypropyl chloride,3-phenylallyloxypropyl chloride, 3- cyclohexylallyloxypropyl chloride,3-p-tolylallyloxypropyl chloride, 3-phenyl- 2-chloroallyloxypropylchloride, 3-phenyl-2-bromoallyloxypropyl chloride, allyloxybutylchloride, propenyloxybutyl chloride, 2- chloroallyloxybutyl chloride,3-chloroallyloxybutyl chloride, 2-bromoallyloxybutyl chloride,3-bromoallyloxybutyl chloride, 2-chloropropenyloxybutyl chloride,butenyloxybutyl chloride, 3-chlorobutenyloxybutyl chloride,3-bromobutenyloxybutyl chloride, 3- phenylallyloxybutyl chloride,3-cyclohexylallyloxybutyl chloride, 3-p-tolylallyloxybutyl chloride,3-phenyl- 2-chloroallyloxybutyl chloride, 3-phenyl-2-bromoallyloxybutylchloride, allyloxypentyl chloride, propenyloxypentyl chloride,2-chloroallyloxypentyl chloride, 3-chloroallyloxypentyl chloride,2-bromoallyloxypentyl chloride, 3-bromoallyloxypentyl chloride,2-chloropropenyloxypentyl chloride, butenyloxypentyl chloride,3-chlorobutenyloxypentyl chloride, 3- bromobutenyloxypentyl chloride,3-phenylallyloxypentyl chloride, 3-cyclohexylallyloxypentyl chloride,3-ptolylallyloxypentyl chloride, 3-phenyl-2-chloroallyloxypentylchloride, 3-phenyl-Z-bromoallyloxypentyl chloride, etc.

The aforementioned alkenyloxyalkyl halides are condensed with alkylphosphites in which the alkyl substituent may contain from one to aboutfive carbon atoms. Specific examples of these compounds will includetrimethylphosphite, triethylphosphite, tripropylphosphite,triisopropylphosphite, tributylphosphite, tri-t-butylphosphite,triamylphosphite, tri-sec-amylphosphite, etc. It is to be understoodthat the aforementioned specific examples of the alkenyloxyalkyl halidesand alkyl phosphites are only representative of the class of compoundswhich may be used, and that the present invention is notnecessarilylimited thereto.

The condensation of the two reactants is effected at condensationconditions within the range hereinbefore set forth in the presence of asubstantially inert organic solvent, if one is employed in the reaction.Some specific examples of these organic solvents which may be used, ifso desired, will include dimethylformamide, diethylformamide,dipropylformamide, dimethylacetamide, diethylacetamide,dipropylacetamide, etc. It is also contemplated that other solvents suchas alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol,isopropyl alcohol, etc.; aromatic solvents such as benzene, toluene,xylenes, ethylbenzene, etc.; paraffinic solvents such as n-heptane,n-hexane, cyclopentane, methylcyclopentane, cyclohexane, etc., or simpleethers such as dimethyl ether, diethyl ether, dipropyl ether may also beused at elevated pressures although not necessarily with equivalentresults.

The compound which results from the condensation of the alkenyloxyalkylhalide and the trialkyl phosphite which comprises a dialkyl ester of analkenyloxyalkylphosphonate is then subjected to a halogenation step bytreating said phosphonate with a chlorinating agent or a brominatingagent comprising hydrogen bromide, elemental bromine, hydrogen chlorideor elemental chlorine in the presence of an organic solvent athalogenation conditions. These halogen conditions will include atemperature ranging from about 0C. up to about C. or more, the preferredtemperature being that of the reflux temperature of the particularsolvent which is employed in the reaction at atmospheric pressure. Uponcompletion of the addition of the halogenating agent the solvent whichis employed in the process is removed by conventional means and thedesired product is recovered. Examples of solvent which may be employedin the halogenation process will include halo-substituted alkanes suchas chloroform, carbon tetrachloride, or aromatic solvents such asbenzene, chlorobenzene, bromobenzene, etc.

The process for preparing the aforementioned novel compositions ofmatter may be effected in any suitable manner and may comprise either abatch or continuous type operation. For example, when a batch typeoperation is used a quantity of the starting materials comprising thealkenyloxyalkyl halide and the trialkyl phosphite are placed in anappropriate apparatus such as a flask provided with heating, stirringand reflux means. In addition, the flask will also contain theparticular solvent which is to be employed. Generally speaking, thereactants are present in the reaction mixture in a molar ratio. Thereactor is then heated tothe desired operating temperature which, ashereinbefore set forth, preferably constitutes the reflux temperature ofthe particular solvent which is employed in the reaction. Thecondensation is allowed to proceed at reflux temperature for apredetermined period of time which may range from about 0.5 up to about10 hours or more in duration, the end of the reaction being attainedwhen there is a cessation of the evolution of alkyl chloride. Thereaction mixture is recovered and subjected to fractional distillationwhereby the desired product'is separated from solvent, unreactedstarting materials and/or unwanted side reactions which may haveoccurred during the condensation period.

The dialkyl ester of an alkenyloxyalkylphosphonate which constitutes thedesired reaction product of the above condensation is then placed in asecond reaction vessel also provided with heating or cooling, stirringand reflux means. In addition, the desired solvent of the typehereinbefore set forth is also present in this reactor. Following thisthe halogenating agent is slowly added to the reactor for apredetermined period of time and the reactor is heated to the refluxtemperature of the particular solvent. it is contemplated within thescope of this invention that the halogenating agent, if in elementalform, may be added as a solution in the same solvent which is present inthe reaction vessel. After the addition of the halogenating agent hasbeen completed, usually in an equimolar amount to the dialkyl ester ofan alkenyloxyalkylphosphonate which is present in the reactor, thereaction mixture is refluxed for an additional period, the total contacttime ranging from 1 to about 10 hours or more in duration. Uponcompletion of the halogenation reaction heating is discontinued and thereaction mixture is recovered from the apparatus. This reaction mixtureis then subjected to distillation whereby the solvent is separated andthe desired product comprising the diester of the polyhalosubstitutedalkyloxyalkylphosphonate.

It is also contemplated within the scope of this invention that thepreparation of the desired novel compositions of matter may beaccomplished by utilizing a continuous manner of operation, although notnecessarily with equivalent results. When such a type of operation isused the starting materials comprising the alkenyloxyalkyl halide andthe trialkyl phosphite are continuously charged to a reaction vesselwhich is maintained at the proper operating conditions of temperatureand pressure. If so desired, the solvent in which the reaction iseffected may be admixed with one or both of the starting materials priorto entry into said reactor or, in the alternative, said solvent may becharged to the reactor through a separate line. Upon completion of thedesired residence time the reactor effluent is continuously withdrawnand subjected to separation means such as fractional distillationwhereby the desired product comprising the diester of analkenyloxyalkylphosphonate is separated from solvent and unreactedstarting materials, the latter two being recycled to form a portion ofthe feed stock, while the former is charged to a second reaction vesselalso maintained at the proper operating conditions of temperature andpressure. In this second reactor the halogenating agent is alsocontinuously charged at a predetermined rate. In addition, the solventin which the reaction is effected may be charged to the reactor througha separate line or admixed with the diester of thealkenyloxyalkylphosphonate prior to entry into said reactor and theresulting solution charged thereto through a single line. Uponcompletion of the desired residence time the reactor effluent from thesecond reactor is continuously discharged and again subjected toconventional separation means such as, for example, fractionaldistillation whereby the desired diester of the polyhalo-substitutedalkyloxyalkylphosphonate is recovered while the solvent is recycled backto the second reactor.

It is also contemplated within the scope of this invention that thedialkyl esters of alkyloxyalkylphosphonates may be prepared by any othermethod which is known to one skilled in the art. y

The aforementioned novel compositions of matter of the present inventionare utilized, as hereinbefore set forth, as components in thepreparation of finished compounds which will possess flame retardant orfire resistant properties, said dialkyl esters of polyhalo-substitutedalkyloxyalkylphosphonates comprising from about 5 percent to about 50percent of the finished product, the other component of the finishedproduct comprising a polymeric substance. The desired finished productsmay be prepared in any suitable manner such as, for example, by admixingthe compounds in a mixer, by milling the components or by extruding the.component through a suitable apparatus after admixture thereof, theonly criterion being that the two components of the mixture arethoroughly admixed in such a fashion so that the components areuniformly distributed throughout the finished product.

Some representative examples of the compounds comprising the finishedproduct of the present invention will include polypropylene and dimethyl2-chloro- 2,3-dibromopropoxymethylphosphonate, ABS and dimethyl2-chloro-2,3-dibromopropoxymethylphosphonate, polyethylene oxide anddimethyl 2-chloro-2,3-dibromopropoxymethylphosphonate, a polyester anddimethyl 2-chloro-2,3-dibromopropoxymethylphosphonate, polyethylene anddimethyl 2- chloro-2,3-dibromopropoxymethylphosphonate, polyurethane anddimethyl 2-chloro- 2,3dibromopropoxymethylphosphonate,polyphenyleneoxide and dimethyl 2-chloro-2,3-dibromopropoxymethylphosphonate, polypropylene and dimethyl 2,3-dichloropropoxymethylphosphonate, ABS and dimethyl2,3-dichloropropoxymethylphosphonate, polyethylene oxide and dimethyl2,3-dichloropropoxymethylphosphonate, a polyester and dimethyl 2,3-dichloropropoxymethylphosphonate, polyethylene and dimethyl2,3-dichloropropoxymethylphosphonate, polyurethane and dimethyl2,3-dichloropropoxymethylphosphonate, polyphenylene oxide and dimethyl2,3-dichloropropoxymethylphosphonate,

9 polypropylene and diethyl dibromopropoxyethylphosphonate, ABS anddiethyl 3- chloro-Z,3-dibromopropoxyethylphosphonate, polyethylene oxideand diethyl 3-chloro-2,3- dibromopropoxyethylphosphonate, a polyesterand diethyl yethylphosphonate, polyethylene and diethyl 3-chloro-2,3-dibromopropoxyethylphosphonate, polyurethane and diethyl3-chloro-2,3-dibromopropoxyethylphosphonate, polyphenylene oxide anddiethyl 3- chloro-2,3-dibromopropoxyethylphosphonate, polypropylene anddipropyl 2,3-dibromobutoxyethylphosphonate, ABS and dipropyl2,3-dibromobutoxyethylphosphonate, polyethylene oxide and dipropyl2,3-dibromobutoxyethylphosphonate, a polyester and dipropyl2,3-dibromobutoxyethylphosphonate, polyethylene and dipropyl 2,3-dibromobutoxyethylphosphonate, polyurethane and dipropyl2,3-dibromobutoxyethylphosphonate, polyphenylene oxide and dipropyl2,3-dibromobutoxyethylphosphonate, etc. It is to be understood that theaforementioned compounds comprising a mixture of a polymer and aneffective amount of a dialkyl ester of a halo-substitutedalkyloxyalkylphosphonate are only representative of the class ofcompounds which may be prepared and that the present invention is notnecessarily limited thereto.

It is also contemplated within the scope of this invention that thefinished product of the type hereinbefore set forth, that is, a polymerand a dialkyl ester of a polyhalo-substituted alkyloxyalkylphosphonatemay also contain a sufficient amount of a tin and/or an antimonycompound which will act as a synergist for the flame retardant propertyof said finished compound by enhancing the desirable characteristic.Some specific examples of the tin and antimony compounds which may beused will include tin compounds in a tetravalent state such as tindioxide, tin tetrachloride, methyl tin trichloride, ethyl tintrichloride, butyl tin trichloride, dipropyl tin dichloride, trimethyltin chloride, methyl tin triacetate, dipropyl tin diacetate, diethyl tindipropionate, diethyl tin dimaleate, dibutyl tin dimaleate, methyl tintrimaleate, dibenzyl tin dichloride, dimethyl tin sulfide, diethyl tinsulfide, dimethyl tin bis(methylmercaptide), dibutyl tinbis(octylmercaptide), diethoxy tin bis(ethylmercaptide), tintetrakis(methylmercaptide), tin tetrakis(phenylmercaptide), diethyl tinmercaptoacetate, dioctyl tin mercaptoacetate, dihexyl tinmercaptopropionate, dimethyl tin mercaptobutyrate, dioctyl tinmercaptobutyrate, dilauryltin dithiobutyric acid ethyl ester, diethyltin S,S bis(3,5,5-trimethylhexyl mercaptoacetate), dibutyl tin S,S'bis(phenoxyethyl mercaptoaceta te), dibutyl tin S,S' bis(diethyleneglycol laurate mercaptoacetate), etc., antimony trioxide, antimonyoxychloride, etc. It is to be understood that these compounds are onlyrepresentative of the synergistic additives which may be admixed withthe polymer and the phosphonate, and that the present invention is notnecessarily limited thereto.

The following examples are given to illustrate the process of thepresent invention which, however, are not intended to limit thegenerally broad scope of the present invention in strict accordancetherewith.

3-chloro-2,3-'

3-chloro-2,3-dibromopropox- A mixture consisting of 84.6 g. (0.6 mole)of 3- chloroallyloxyrnethyl chloride and 74.4 g. (0.6 mole) of trimethylphosphite along with 8 g. of dimethylacetamide is heated at refluxtemperature for a period of about 7 hours until the evolution of methylchloride ceases. Following this the mixture is subjected to fractionaldistillation under reduced pressure and the desired product comprisingdimethyl 3-chloroallyloxymethylphosphonate is recovered.

A solution of 42.9 g. (0.2 mole) of the dimethyl 3-chloroallyloxymethylphosphonate which is prepared according to the aboveparagraph in 60 cc. of carbon tetrachloride is heated to reflux andthereafter a solution of 32 g. (0.2 mole) of elemental bromine in anadditional 40 cc. of carbon tetrachloride is slowly added dropwise tosaid refluxing solution. Upon completion of the addition of the brominethe solution is refluxed for an additional period of 5 hours, thecompletion of the reaction being signified by the disappearance of thebromine color. Following this the reaction mixture is subjected tofractional distillation to remove carbon tetrachloride solvent, thedesired product comprising dimethyl3-chloro-2,3-dibromopropoxymethylphosphonate being recovered therefrom.

EXAMPLE n In similar manner a mixture of 84.6 g. (0.6 mole) of3-chloroallyloxymethyl chloride and 99.6 g. (0.6 mole) of triethylphosphite along with 10 g. of diethylformarnide is heated to reflux fora period of 7 hours until the evolution of methyl chloride ceases. Theresulting mixture is then subjected to fractional distillation underreduced pressure whereby the desired product comprising diethyl3-chloroallyloxymethylphosphonate is thereby recovered. A solution of48.5 g. (0.2 mole) of the diethyl 3-chloroallyloxymethylphosphonate and60 cc. of carbon tetrachloride is heated to reflux, following which asolution of 32 g. (0.2 mole) of elemental bromine in an additional 40cc. of carbon tetrachloride is slowly added dropwise to the refluxingsolution. Upon completion of the addition of the bromine the solution isrefluxed for an additional period of 5 hours, which completion of thereaction being signified by the disappearance of the bromine color. Thereaction mixture is recovered and subjected to fractional distillationto remove the carbon tetrachloride solvent as well as unreacted startingmaterial, the desired product comprising diethyl3-chloro-2,3-dibromopropoxymethylphosphonate being separated andrecovered.

EXAMPLE III In this example 53.3 g. (0.5 mole) of allyloxymethylchloride and 62.0 g. (0.5 mole) of trimethyl phosphite along with 8 g.of dimethylacetamide are placed in an appropriate apparatus providedwith heating, stirring and reflux means. The solution is heated atreflux for a period of 6.5 hours and thereafter subjected to fractionaldistillation under reduced pressure. The desired product comprisingdimethyl allyloxymethylphosphonate is thereafter recovered. Thereafter36 g. (0.2 mole) of the dimethyl allyloxymethylphosphonate is dissolvedin 60 cc. of carbon tetrachloride and heated to reflux. A solution of 32g.

1 l (0.2 mole) of elemental bromine in an additional 40 cc. of carbontetrachloride is slowly added dropwise to the refluxing solution.Following the completion of the addition of the bromine heating iscontinued at reflux temperature for an additional period of 5 hours. Atthe end of this time the reaction mixture is subjected to fractionaldistillation to remove the solvent, unreacted starting material andundesired side reaction products,

the desired product comprising dimethyl 2,3-dibromopropoxymethylphosplionate being recovered therefrom.

EXAMPLE IV In this example a mixture consisting of 93.0 g. (0.6 mole) of4-chlorobutenyloxymethyl chloride, 74.4 g. (0.6 mole) of trimethylphosphite and 8 g. of dimethylformamide is heated to reflux temperaturefor a period of 7 hours. Upon completion of this reaction period themixture is subjected to fractional distillation under reduced pressureand the desired intermediate compound comprising dimethyl4-chlorobutenyloxymethylphosphonate is recovered. A portioncomprising"45.7 g. (0.2 mole) of the dimethyl4-chlorobutenyloxymethylphosphonate is added to 60 cc. of carbontetrachloride and the resulting solution is then heated to reflux.Thereafter a solution of 32 g. (0.2 mole) of elemental bromine which isin an additional 40 cc. of carbon tetrachloride is slowly added dropwiseto the refluxing solution. Reflux is thereafter continued for anadditional period of 6 hours, the completion of the reaction, as in theabove examples, being signified by the disappearance of the brominecolor. Thereafter the reaction mixture is subjected to fractionaldistillation whereby the desired product comprising dimethyl4-chloro-3,4-dibromobutyloxymethylphosphonate is recovered.

EXAMPLE V The reaction set forth in example III above is repeated, thedifference being that 60.3 g. (0.5 mole) of allyloxyethyl chloride isreacted with 62 g. (0.5 mole) of trimethyl phosphite. The desiredproduct which is recovered by fractional distillation comprises dimethylallyloxyethylphosphonate. This product is then treated with elementalbromine also in a manner similar to that set forth in example lIl abovewhereby, in fractional distillation under reduced pressure to remove thecarbon tetrachloride solvent, the desired product comprising dimethyl2,3-dibromopropoxyethylphosphonate is recovered.

EXAMPLE VI A polyester is prepared in a conventional manner by admixing1 mole of male'ic anhydride, 1 mole of phthalic anhydride, and 2 molesof propylene glycol to a final temperature of 195C. The resultantmixture is admixed with styrene, following which the resultant polyesteris divided into two portions. To one portion of the polyester is added asufficient amount of the compound prepared according to example I above,that is, dimethyl 3-chloro-2,3-dibromopropoxymethylphosphonate, so thatthe finished polyester contains percent of the phosphonate. Thetwo'portions are then each treated with a catalyst and poured into moldsfollowing which the casts are cured in an air oven for 1 hourat atemperature of C. and for 1 hour at C. In order to determine the fireretardancy of the ester containing the phosphonate the casts are burnedin an apparatus similar to that described by C. P. Fennimore and J. F.Martin in the November, 1966 issue of Modern Plastics. The cast whichconsists only of thepolyester has an oxygen index (the lowest molefraction of oxygen sufficient to maintain combustion) of n =0. 187. Incontrast to this the oxygen index of the polyester cast which containsthe dimethyl 3-chloro- 2,3-dibromopropoxymethylphosphonate has an oxygenindex greatly in excess of this number.

EXAMPLE VII In this example polyethylene is milled with dimethyl3-chloro-2,3-dibromopropoxymethylphosphonate which is prepared accordingto the precess set forth in example ll above so that the finishedproduct will contain 15 percent by weight of the phosphonate. Thereafterthe resulting compound comprising the polyethylene and the diethyl3-chloro-2,3- dibromopropoxymethylphosphonate is pressing into sheetswhich contain a glass cloth in the center of the sheet to preventdrooping during the combustion. Likewise, a commercial polypropyleneformulation, per se,is milled and also pressed into'sheets of similarconfiguration. Strips are cut from these sheets and then subjected to aflammability test similar in nature to that described in example VIabove. The results of these tests discloses the fact that the oxygenindex of the polyethylene containing the phosphonate diester is greatlyin excess over the oxygen index of the untreated polyethylene. Inaddition, it is also found that the rate of burning of the treatedpolyethylene is much slower that that which is exhibited by theuntreated polyethylene.

EXAMPLE VIII In this example a commercialacrylonitrile-butadiene-styrene formulation (ABS) is admixed with asufficient amount of dimethyl 2,3-dibromopropoxymethylphosphonate sothat the finished product will contain 15 percent by weight of thephosphonate. The mixture is then extruded as rods having a diameter of0.5 cm. In addition, another rod of similar diameter is prepared whichcontains only the commercial ABS formulation. The rods are then burnedin a flammability test utilizing the apparatus described in theaforesaid November, 1966 issue of Modern Plastics magazine. The rodwhich contains only the commercial ABS formulation has an oxygen indexof 0.183 while the 0xygen index of the ABS formulation containing thephosphonate has greatly in excess of this number.

EXAMPLE IX EXAMPLE X In this example a commercial polypropylene ismilled with diethyl 3-chloro-2,3-dibromopropoxymethylphosphonate in amanner similar to that described in example VII, the finished productcontaining percent by weight of the phosphonate. This compound is thenformed into a strip which contains a glass cloth in the center thereofto prevent dripping during the combustion test. A second stripconsisting of only polypropylene is also prepared and thereafter bothstrips are subjected to the flammability test referred to in example VIabove. The oxygen index of the strip which contains only polypropyleneis 0.181 while the strip which consists of a mixture of thepolypropylene and the phosphonate compound possesses a greater thanaverage oxygen index and also exhibits a burning rate which is farslower than the strip which contains no flame retardant.

I claim as my invention:

1. A composition of matter comprising a diester of a halo-substitutedalkyloxyalkylphosphonate having the formula:

in which R is an alkyl radical of from one to about five carbon atoms, Rand R" are independently selected from the group consisting of hydrogen,halogen, lower alkyl of from one to five carbon atoms, and cycloalkyl,aryl, aralkyl, and alkaryl compounds containing up to seven carbon atomsand halogenated derivatives thereof, n is an integer of from 1 to 5, andX is hydrogen or halogen atoms, at least two of X being halogen atoms.

2. The novel composition of matter in claim 1 being dimethyl3-chloro-2,3-dibromopropoxymethylphosphonate.

3. The novel composition of matter in claim 1 being diethyl3-chloro-2,3-dibromopropoxymethylphosphonate.

4. The novel composition of matter in claim 1 being dimethyl2,3-dibromopropoxymethylphosphonate.

5. The novel composition of matter in claim 1 being dimethyl2,3-dibromopropoxyethylphosphonate.

6. The novel composition of matter in claim 1 being dimethyl4-chloro-3,4-dibromobutoxymethylphosphonate.

2. The novel composition of matter in claim 1 being dimethyl3-chloro-2,3-dibromopropoxymethylphosphonate.
 3. The novel compositionof matter in claim 1 being diethyl3-chloro-2,3-dibromopropoxymethylphosphonate.
 4. The novel compositionof matter in claim 1 being dimethyl 2,3-dibromopropoxymethylphosphonate.
 5. The noVel composition of matter inclaim 1 being dimethyl 2, 3-dibromopropoxyethylphosphonate.
 6. The novelcomposition of matter in claim 1 being dimethyl4-chloro-3,4-dibromobutoxymethylphosphonate.